AS33661 — CMCS

AS33661 announces 164 IPv4 prefixes covering 630,272 addresses and 43 IPv6 prefixes.

About this network

CMCS is the AS handle for Comcast Cable Communications, LLC, a major US cable operator.

What it's used for

• The space carries residential cable internet access, evidenced by reverse DNS entries like c-76-148-64-0.hsd1.fl.comcast.net and netnames such as NAPLES-CPE-18 and WESTFLORIDA-15.
• With 630,528 IPv4 addresses announced across 165 prefixes and only 23 observed neighbours, the high address-to-neighbour ratio indicates a large access/eyeball network rather than a transit provider.

Notable

• Registrants consistently identify as Comcast Cable Communications, LLC or its historical variants (Inc., IP Services), aligning with the announcer.
• The address inventory is finely subdivided into regional blocks (e.g., Naples, West Florida, Lake County), reflecting site-by-site segmentation of a corporate estate.
• The AS was first seen in RIS in 2007, consistent with Comcast's expansion of its IP services infrastructure.

This description is AI-generated, best-effort context — not authoritative, and provided without any guarantee of accuracy.

Announced prefixes

• 23.31.176.0/20
• 24.124.134.0/23
• 50.78.212.0/22
• 50.79.216.0/22
• 50.184.164.0/22
• 50.185.48.0/21
• 50.191.0.0/20
• 50.192.16.0/20
• 50.192.208.0/21
• 50.194.212.0/22
• 50.197.232.0/21
• 50.218.97.0/24
• 50.220.33.0/24
• 50.226.0.0/24
• 50.227.97.0/24
• 50.236.155.0/24
• 50.237.76.0/24
• 50.245.64.0/20
• 50.245.88.0/22
• 50.251.96.0/20
• 50.252.176.0/22
• 50.254.208.0/21
• 64.139.74.0/23
• 66.208.226.0/24
• 67.162.160.0/20
• 67.174.0.0/19
• 68.84.240.0/20
• 68.85.59.0/24
• 68.85.64.0/24
• 68.85.96.0/22
• 68.85.210.0/23
• 68.85.212.0/23
• 68.85.238.0/23
• 68.86.59.0/24
• 68.87.74.0/24
• 68.87.236.0/22
• 69.136.16.0/20
• 69.137.0.0/20
• 69.137.192.0/20
• 69.137.240.0/20
• 69.138.112.0/20
• 69.138.128.0/20
• 69.139.32.0/19
• 69.139.170.0/23
• 69.139.188.0/23
• 69.241.11.0/24
• 69.241.115.0/24
• 69.242.240.0/20
• 69.244.240.0/20
• 69.247.32.0/19
• 69.247.80.0/20
• 69.247.240.0/20
• 69.252.38.0/23
• 69.252.44.0/23
• 69.252.54.0/24
• 69.252.68.0/24
• 69.254.32.0/19
• 69.254.112.0/20
• 70.88.32.0/22
• 70.88.56.0/21
• 70.88.85.0/24
• 70.89.74.0/24
• 70.90.64.0/21
• 70.90.254.0/23
• 70.91.160.0/24
• 70.91.208.0/23
• 71.25.128.0/20
• 71.27.176.0/20
• 71.200.192.0/18
• 71.203.0.0/18
• 71.203.80.0/20
• 71.226.16.0/20
• 71.226.80.0/20
• 71.228.64.0/19
• 74.92.181.0/24
• 74.93.32.0/22
• 74.93.46.0/23
• 74.93.60.0/23
• 74.93.124.0/22
• 74.95.49.0/24
• 74.95.60.0/22
• 74.95.128.0/23
• 74.95.144.0/23
• 75.144.12.0/22
• 75.144.104.0/22
• 75.145.0.0/21
• 75.145.194.0/23
• 75.146.86.0/24
• 75.146.136.0/23
• 75.147.144.0/20
• 75.148.104.0/22
• 75.151.32.0/20
• 75.151.64.0/22
• 75.151.75.0/24
• 76.26.176.0/20
• 76.26.224.0/19
• 76.29.128.0/19
• 76.96.10.0/23
• 76.96.92.0/23
• 76.101.0.0/16

and 107 more.

Upstream networks

• AS7922 Comcast Cable Communications, LLC

Downstream networks

• AS46576 Loews Hotels at Universal Orlando
• AS63402 Universal Orlando
• AS26876 chico's fas inc
• AS6931 Ringling College of Art and Design
• AS63264 Alternative Choice Wireless, LLC
• AS46999 Crews Banking Corporation
• AS54113 Fastly, Inc.
• AS53937 Sarasota Memorial Hospital
• AS54119 WhiteSky Communications, LLC.
• AS36040 Google LLC
• AS36763 Hearst-Argyle Television, Inc.
• AS396910 Lee County Port Authority
• AS401671 ACCESSPARKS LLC
• AS398743 The Nemours Foundation
• AS395036 City of Sanibel
• AS398641 Community Health Centers, Inc.
• AS396291 NCH Healthcare System, Inc.
• AS395659 SeaWorld Parks & Entertainment, Inc.
• AS30415 Sarasota County Government
• AS23542 Florida's Natural Growers, Inc.

Adjacent networks

• AS7922 Comcast Cable Communications, LLC
• AS46576 Loews Hotels at Universal Orlando
• AS63402 Universal Orlando
• AS17035 NBCUniversal
• AS26876 chico's fas inc
• AS63264 Alternative Choice Wireless, LLC
• AS6931 Ringling College of Art and Design
• AS46999 Crews Banking Corporation
• AS54113 Fastly, Inc.
• AS53937 Sarasota Memorial Hospital
• AS54119 WhiteSky Communications, LLC.
• AS36763 Hearst-Argyle Television, Inc.
• AS36040 Google LLC
• AS396910 Lee County Port Authority
• AS401671 ACCESSPARKS LLC
• AS398743 The Nemours Foundation
• AS395036 City of Sanibel
• AS398641 Community Health Centers, Inc.
• AS395659 SeaWorld Parks & Entertainment, Inc.
• AS396291 NCH Healthcare System, Inc.
• AS30415 Sarasota County Government
• AS23542 Florida's Natural Growers, Inc.
• AS53445 The Villages Health